Columbia Public Schools has changed the way it is calculating the 14-day rate for COVID-19 cases.
During a meeting of the Columbia School Board on Monday, Superintendent Peter Stiepleman explained the changes in the equation used to determine the 14-day rate.
To calculate the rate, the district totals the number of new cases in the past two weeks, then divides that total by the population divided by 10,000, according to explanatory information on the Learning Mode Matrix 14-Day COVID Tracker.
This gives the 14-day rate of cases per 10,000 people. The school district uses this figure to help calculate the viability of in-person teaching.
The U.S. Census Bureau estimated that last year, the year for which the most recent data was available, the city of Columbia’s population was just over 123,000. However, the population of the district, which is larger than the city itself, was about 154,000.
The district had been using an estimate of 130,000 for the city population. On Monday, the board agreed to Stiepleman’s request to expand the population base to include students who live outside the city but attend district schools.
The change lowered the 14-day rate per 10,000 cases Monday from 71.5 to 61.9. That was still well above the 50 per 10,000 cases the district set as one marker in determining whether to go all-virtual.
On Wednesday, there were 154 new cases in the areas that make up the district, meaning 72.5 cases per 10,000 people, according to the tracker.
Countywide, the number of new cases was 168, yet another new single-day high.